I never saw the internals, but from a coder's standpoint the thread switches were really fast, with low latency. Compared with Windows NT and OS/2, way faster

I never saw the internals, but from a coder's standpoint the thread switches were really fast, with low latency. Compared with Windows NT and OS/2, way faster on the same hardware. I don't have a comparison with Linux, as it was just getting started back then (IIRC, Slackware was the leading distro of the time)